Colorant for foliage of humic and/or fulvic acid, and dye

ABSTRACT

The invention relates to a colorant composition comprising humic acid and/or fulvic acid and a water soluble dye. The invention in particular relates to a colorant composition to be used for turf.

FIELD OF THE INVENTION

The present invention relates to a colorant composition. In particular,the present invention relates to a colorant composition suitable forcolouring foliage and in particular turf grass. Although the presentinvention will be described with particular reference to thisapplication, it will be appreciated that the composition may find otherapplications and no limitation is intended thereby.

BACKGROUND OF THE INVENTION

Turf grasses are widely used in recreational areas, parks, golf courses,bowling greens, athletic fields and domestic lawns. There is a demandfor turf to have a uniform green colour so as to provide a pleasingappearance. This is particularly so for televised sporting events whereit is desirable that a playing field have a healthy looking and uniformgreen colour. However, under adverse conditions such as drought andfrosts, grass can lose its natural colour and in some circumstanceschange to an undesirable appearance. Turf colorants that can impart agreen colour to discoloured turf have been developed with a view toartificially returning a playing field to a desirable colour or tosimply make the turf appear more robust and healthy. Green colorants arealso used to colour sand and in particular, divot sand as used on golfcourses.

A green colorant that is widely used commercially is a pigment basedcolorant comprising a water insoluble pigment suspended in an aqueoussolution. In practice, application problems may be experienced whenapplying pigment based colorants. Such problems include blockage ofapplication nozzles and equipment cleaning difficulties.

Other colorants for use in the agricultural industry are also available.Such colorants are based on water soluble dyes. As the dyes are watersoluble, the above-mentioned application difficulties associated withpigment based colorants are generally not experienced. The dye basedcolorants typically contain blue or red dyes and are used as markers forspraying herbicides, insecticides and the like. Blue colorants are alsoused to impart a blue colour to water features. The blue dyes may alsobe used on turf but impart a blue colour, which is generally notconsidered desirable.

However, there are some concerns regarding repeated use of pigments onplaying fields and the like for a number of reasons. First, there arepotential toxicity problems to those spraying the dyes and those playingon, or otherwise using the field. Although pigments commonly used tocolour turf are considered safe to human health, there are few, if any,studies on long term exposure of these chemicals. Still further, theremay be potential environmental hazards associated with build up of thesechemicals in the environment as a result of repeated spraying. Generallya respray is necessary whenever the grass is cut. In some cases, aplaying field may be sprayed at weekly or fortnightly intervalsimmediately prior a match or game being played on the field.

It is therefore an object of the present invention to provide analternative colorant composition that is suitable for use on turf orother suitable surfaces.

DESCRIPTION OF THE INVENTION

According to a first broad form of the invention there is provided acolorant composition comprising humic acid, fulvic acid or a mixturethereof and a water soluble dye.

The present inventor has surprisingly and unexpectedly discovered thatby adding humic and/or fulvic acid to a colorant, the colour of theresulting composition may be intensified and/or modified.

Humic acids are the fraction of humic substances that are not soluble inwater under acidic conditions (less than about 2) but are soluble athigher pH values. Fulvic acids are soluble under all pH conditions.

Humic acid and fulvic acid are typically available and used in the formof aqueous solutions. Alternatively, these materials are available insolid form such as powder or granules. Typically, the composition isprepared by combining the ingredients with water to provide aconcentrated liquid solution. This solution may be diluted prior to use.Alternatively, the components may be mixed in dry form. The dry mixturemay be dissolved to provide a concentrate for shipping and sale, or maybe dissolved prior to use.

Preferred dyes for use in the composition of the present invention areanionic dyes. Whilst not wishing to be bound by theory it is believedthat the anionic dyes are less likely to precipitate in the presence ofanionic components of humic and/or fulvic acid salts.

Especially preferred dyes are those containing organic acid groups,e.g., sulfonic, sulfamic, phosphoric, carboxylic, etc., or their salts.Acid dyes are commonly alkali metal such as sodium or potassium, orammonium salts of an organic acid. Preferred dyes are salts of sulfonicacids such as acid blue 62 (Sodium1-amino-4-(cyclohexylamino)-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate);acid blue 74 (Disodium5,5′-(2-(1,3-dihydro-3-oxo-2H-indazol-2-ylidene)-1,2-dihydro-3H-indol-3-one)disulphonate);acid blue 1 (Hydrogen[4-[4-(diethylamino)-2′,4′-disulphonatobenzhydrylidene]cyclohexa-2,5-dien-1-ylidene]diethylammonium,sodium salt); acid blue 185 (CAS 1330-39-8); acid blue 9 (Dihydrogen(ethyl)[4-[4-[ethyl(3-sulphonatobenzyl)]amino]-2′-sulphonatobenzhydrylidene]cyclohexa-2,5-dien-1-ylidene](3-sulphonatobenzyl)ammoniumor disodium salt); acid green 1 (Trisodiumtris[5,6-dihydro-5-(hydroxyimino)-6-oxonaphthalene-2-sulphonato(2-)-N5,O6]ferrate(3-)and acid green 50 (Hydrogen[4-[4-(dimethylamino)-a-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium,monosodium salt) or mixtures of any two or more thereof. Other suitablecolouring agents are the phthalocyanine pigments of which Copperphthalocyanine blue or Pigment blue 15 is an example.

Especially preferred are the acid blue dyes, of which a sample ismentioned above. Such blue dyes are often used to impart a blue colourto ponds and water features. Blue dyes are also used as marker dyes toassist in identifying which areas of vegetation have been sprayed with aherbicide, insecticide or the like. Blue dyes may also be used as basesfor green colorants. A yellow dye such as tartrazine (acid yellow 23)may be combined with the blue to provide a desired green colour.

It will be appreciated that any combination of two or more colorants mayalso be used in the composition of the present invention. The selectionand formulation of such colorants will depend upon the desired result.This may be determined by one of skill in the art.

The present inventor has also very surprisingly and unexpectedlydiscovered that the combination of humic and/or fulvic acid with a bluedye produces a green colorant without requiring the addition of furtheryellow dyes or colouring agents.

The relative amounts of humic and/or fulvic acid to the colorant may bevaried depending upon the desired colour and end use. Suitably thecomposition may comprise between about 50:1 to about 1:30, preferablybetween about 30:1 to about 1:3 parts by weight of humic and/or fulvicacid and colorant. Similarly, the actual amounts of dye and humic and/orfulvic acid in the composition may be varied according to the nature ofthe dye, desired colour and end use. Suitably the composition issupplied in a concentrated form and diluted for application. Suitably acomposition may include between about 10 to about 30 wt % humic and/orfulvic acid.

The composition may also include other one or more additives known inthe art such as stabilizers, stickers, surfactants or other surfaceactive agents, fertilizers, insecticides, fungicides, pesticides,herbicides, wetting agents and the like.

Preferably, the composition includes one or more fertilizers, typicallyone or more water soluble fertilizers. Suitable fertilizers,combinations and amounts thereof are known in the art of horticultureand in particular, turf management. Suitable fertilizers includenitrogen sources such as urea, ammonia sulfate, urea formaldehyde;phosphate and potassium. A preferred fertilizer is urea.

The composition may also include a source of iron in the form of ironsulfate or chelated iron such as ferric EDTA.

The composition may also include a surfactant that may assist thecomposition to adhere or stick to the grass.

Surfactants suitable for such use include alcohol ethoxylates, nonyl,phenyl ethoxylates, polyethylene/polypropylene block copolymers.

The present invention also relates to a method for imparting colour tofoliage. The foliage is typically turf grass but may be any othersuitable foliage.

According to a further broad form of the invention, there is provided amethod of imparting a colour to foliage, the method including applying acomposition of the first broad form to the foliage.

The composition may be applied by any suitable means known in the art,such as by spraying.

By way of example only, the present invention will now be described withreference to the following Examples.

A composition was prepared by mixing an aqueous solution of 120 kg humicand/or fulvic acid (calculated as dry humic and/or fulvic acid) with 7.5kg of a dye known as “Brilliant Blue” with 1000 kg water. (It isbelieved that the brilliant blue contains the dye acid blue 9). Thecomposition was sprayed onto a turf grass field at a rate of 0.2 L-1 Lper 100 m² diluted in 2-40 L water. This equates to about 24 g to about120 humic and/or fulvic acid per 100 m and 1.5 to 7.5 g dye. A preferredrate of application is 0.5-1 L per 100 m² diluted in 5-10 L water. Agreen colour was imparted to the field.

A further composition was prepared in the same manner but with thefurther addition of 150 kg urea and 35 kg ferric EDTA to the 1000 kgwater. Comparative trials were conducted by using aqueous compositionscomprising either humic and/or fulvic acid or dye on their own in thesame amounts and application rates as used above. In both cases, novisible green colour was imparted to the field.

A further trial was conducted using a green paint conventionally used tocolour a playing field. 90 kg of the paint was diluted in 1000 kg waterbefore spraying as above.

It was observed that in the case of the composition of the invention andthe commercially available green colorant, a green colour was impartedto the field. However, the composition of the invention achieved asimilar colour intensity with significantly less colorant than thatrequired using the conventional formulation.

Still further, it was surprisingly and unexpectedly observed that thecomposition of the invention imparted a green colour that was observedto be a far more natural colour and representative of a naturally greenfield. On the other far more natural colour and representative of anaturally green field. On the other hand, the conventional green paintimparted a colour that was observed to be somewhat artificial ascompared with a natural grass colour. The present inventor is unaware ofa commercially available green turf colorant that imparts a naturalgreen colour. A further advantage of being able to impart a naturalgreen colour to a field is that treated turf can more easily blend inwith untreated turf. Such a situation may arise where there are patchesof damaged turf to be repaired. Generally, with prior art compositionsit is necessary to also spray untreated turf to provide a uniform greencolour. This may not be necessary with the preferred composition of theinvention.

Still further, the inventive composition was not observed to have any ofthe aforementioned application difficulties associated with the use of apigment based colorant, i.e. clogging and/or blockage of applicatornozzles and the like. The present inventor is also unaware of acommercially available green turf colorant that is based on a dye asopposed to a pigment.

It may be seen that the composition of the present invention allowssignificantly less dye material to be used in order to impart a level ofcolour comparative to conventional formulations. This ability todecrease the levels of chemical colorants required can reduce potentialhealth risks for workers applying the chemicals, can reduce the build upof chemical residues in the environment and further, due to thedecreased amount of colorant can reduce costs. (Humic and/or fulvic acidbeing less expensive than the available colorants).

In the specification the term “comprising” shall be understood to have abroad meaning similar to the term “including” and will be understood toimply the inclusion of a stated integer or step or group of integers orsteps but not the exclusion of any other integer or step or group ofintegers or steps. This definition also applies to variations on theterm “comprising” such as “comprise” and “comprises”.

It will be appreciated that various changes and modifications may bemade to the invention as described herein without departing from thespirit and scope thereof.

1. An aqueous green foliage colorant composition consisting of humicacid, fulvic acid, water and a water soluble acid blue dye.
 2. Anaqueous green foliage colorant composition consisting of humic acid,fulvic acid, water, a water soluble anionic acid blue dye, andoptionally a water soluble fertilizer, a soluble surfactant and a sourceof iron.
 3. The composition of claim 2 wherein the ratio of humic acidand fulvic acid to colorant is between about 50:1 to about 1:3 parts byweight.
 4. The composition of claim 2, wherein said composition is in aform suitable for spray application to turf.
 5. The composition of claim2, wherein the source of iron is ferric EDTA.
 6. The composition ofclaim 2, wherein the fertilizer is urea.
 7. An aqueous green foliagecolorant composition consisting of humic acid, fulvic acid, water and awater soluble acid blue dye and additives selected from the groupconsisting of surface active agents selected from alcohol ethoxylates,phenyl ethoxylates and polyethylene/polypropylene block copolmers, andfertilizers selected from ammonia sulfate, formaldehyde, phosphate,potassium and urea.
 8. A method of imparting a colour to foliage, themethod including applying a composition of claim 2 to the foliage. 9.The method of claim 8, wherein the foliage is turf grass.
 10. The methodof claim 9, wherein between about 24 to about 120 g humic and fulvicacid and between about 1.5 to about 7.5 g dye are applied per 100 m2turf grass.
 11. The method of claim 8, wherein the dye contains anorganic acid group or a salt thereof.
 12. The method of claim 8, whereinthe dye is a salt of a sulfonic acid.
 13. The method of claim 8, whereinthe dye is selected from the group consisting of acid blue 62 (Sodium1-amino-4-(cyclohexylamino)-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate); acid blue 74 (Disodium 5, 5′-(2 -(1,3-dihydro-3-oxo-2H-indazol-2-ylidene)-1,2-dihydro-3H-indol-3-one)disulphonate);acid blue 1(Hydrogen[4-[4-(diethylamino)-2′,4′-disulphonatobenzhydrylidene]cyclohexa-2,5-dien-1-ylidene]diethylammonium, sodium salt); acid blue 185 and acidblue 9 (Dihydrogen(ethyl)[4-[4-[ethyl(3-sulphonatobenzyl)]amino]-2′-sulphonatobenzhydrylidene]cyclohexa-2,5-dien-1-ylidene](3-sulphonatobenzyl)ammoniumor disodium salt) or mixtures of any two or more thereof.
 14. The methodof claim 8, wherein the ratio of humic acid and fulvic acid to colorantis between about 50:1 to about 1:3 parts by weight.
 15. The method ofclaim 8, wherein the water soluble fertilizer is present.
 16. The methodof claim 8, wherein the soluble surfactant is present.